/*!
 * Jinja Templating for JavaScript v0.1.8
 * https://github.com/sstur/jinja-js
 *
 * This is a slimmed-down Jinja2 implementation [http://jinja.pocoo.org/]
 *
 * In the interest of simplicity, it deviates from Jinja2 as follows:
 * - Line statements, cycle, super, macro tags and block nesting are not implemented
 * - auto escapes html by default (the filter is "html" not "e")
 * - Only "html" and "safe" filters are built in
 * - Filters are not valid in expressions; `foo|length > 1` is not valid
 * - Expression Tests (`if num is odd`) not implemented (`is` translates to `==` and `isnot` to `!=`)
 *
 * Notes:
 * - if property is not found, but method '_get' exists, it will be called with the property name (and cached)
 * - `{% for n in obj %}` iterates the object's keys; get the value with `{% for n in obj %}{{ obj[n] }}{% endfor %}`
 * - subscript notation `a[0]` takes literals or simple variables but not `a[item.key]`
 * - `.2` is not a valid number literal; use `0.2`
 *
 */
/*global require, exports, module, define */

(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
      typeof define === 'function' && define.amd ? define(['exports'], factory) :
          (global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.jinja = {}));
})(this, (function (jinja) {
  "use strict";
  var STRINGS = /'(\\.|[^'])*'|"(\\.|[^"'"])*"/g;
  var IDENTS_AND_NUMS = /([$_a-z][$\w]*)|([+-]?\d+(\.\d+)?)/g;
  var NUMBER = /^[+-]?\d+(\.\d+)?$/;
  //non-primitive literals (array and object literals)
  var NON_PRIMITIVES = /\[[@#~](,[@#~])*\]|\[\]|\{([@i]:[@#~])(,[@i]:[@#~])*\}|\{\}/g;
  //bare identifiers such as variables and in object literals: {foo: 'value'}
  var IDENTIFIERS = /[$_a-z][$\w]*/ig;
  var VARIABLES = /i(\.i|\[[@#i]\])*/g;
  var ACCESSOR = /(\.i|\[[@#i]\])/g;
  var OPERATORS = /(===?|!==?|>=?|<=?|&&|\|\||[+\-\*\/%])/g;
  //extended (english) operators
  var EOPS = /(^|[^$\w])(and|or|not|is|isnot)([^$\w]|$)/g;
  var LEADING_SPACE = /^\s+/;
  var TRAILING_SPACE = /\s+$/;

  var START_TOKEN = /\{\{\{|\{\{|\{%|\{#/;
  var TAGS = {
      '{{{': /^('(\\.|[^'])*'|"(\\.|[^"'"])*"|.)+?\}\}\}/,
      '{{': /^('(\\.|[^'])*'|"(\\.|[^"'"])*"|.)+?\}\}/,
      '{%': /^('(\\.|[^'])*'|"(\\.|[^"'"])*"|.)+?%\}/,
      '{#': /^('(\\.|[^'])*'|"(\\.|[^"'"])*"|.)+?#\}/
  };

  var delimeters = {
      '{%': 'directive',
      '{{': 'output',
      '{#': 'comment'
  };

  var operators = {
      and: '&&',
      or: '||',
      not: '!',
      is: '==',
      isnot: '!='
  };

  var constants = {
      'true': true,
      'false': false,
      'null': null
  };

  function Parser() {
      this.nest = [];
      this.compiled = [];
      this.childBlocks = 0;
      this.parentBlocks = 0;
      this.isSilent = false;
  }

  Parser.prototype.push = function (line) {
      if (!this.isSilent) {
          this.compiled.push(line);
      }
  };

  Parser.prototype.parse = function (src) {
      this.tokenize(src);
      return this.compiled;
  };

  Parser.prototype.tokenize = function (src) {
      var lastEnd = 0, parser = this, trimLeading = false;
      matchAll(src, START_TOKEN, function (open, index, src) {
          //here we match the rest of the src against a regex for this tag
          var match = src.slice(index + open.length).match(TAGS[open]);
          match = (match ? match[0] : '');
          //here we sub out strings so we don't get false matches
          var simplified = match.replace(STRINGS, '@');
          //if we don't have a close tag or there is a nested open tag
          if (!match || ~simplified.indexOf(open)) {
              return index + 1;
          }
          var inner = match.slice(0, 0 - open.length);
          //check for white-space collapse syntax
          if (inner.charAt(0) === '-') var wsCollapseLeft = true;
          if (inner.slice(-1) === '-') var wsCollapseRight = true;
          inner = inner.replace(/^-|-$/g, '').trim();
          //if we're in raw mode and we are not looking at an "endraw" tag, move along
          if (parser.rawMode && (open + inner) !== '{%endraw') {
              return index + 1;
          }
          var text = src.slice(lastEnd, index);
          lastEnd = index + open.length + match.length;
          if (trimLeading) text = trimLeft(text);
          if (wsCollapseLeft) text = trimRight(text);
          if (wsCollapseRight) trimLeading = true;
          if (open === '{{{') {
              //liquid-style: make {{{x}}} => {{x|safe}}
              open = '{{';
              inner += '|safe';
          }
          parser.textHandler(text);
          parser.tokenHandler(open, inner);
      });
      var text = src.slice(lastEnd);
      if (trimLeading) text = trimLeft(text);
      this.textHandler(text);
  };

  Parser.prototype.textHandler = function (text) {
      this.push('write(' + JSON.stringify(text) + ');');
  };

  Parser.prototype.tokenHandler = function (open, inner) {
      var type = delimeters[open];
      if (type === 'directive') {
          this.compileTag(inner);
      } else if (type === 'output') {
          var extracted = this.extractEnt(inner, STRINGS, '@');
          //replace || operators with ~
          extracted.src = extracted.src.replace(/\|\|/g, '~').split('|');
          //put back || operators
          extracted.src = extracted.src.map(function (part) {
              return part.split('~').join('||');
          });
          var parts = this.injectEnt(extracted, '@');
          if (parts.length > 1) {
              var filters = parts.slice(1).map(this.parseFilter.bind(this));
              this.push('filter(' + this.parseExpr(parts[0]) + ',' + filters.join(',') + ');');
          } else {
              this.push('filter(' + this.parseExpr(parts[0]) + ');');
          }
      }
  };

  Parser.prototype.compileTag = function (str) {
      var directive = str.split(' ')[0];
      var handler = tagHandlers[directive];
      if (!handler) {
          throw new Error('Invalid tag: ' + str);
      }
      handler.call(this, str.slice(directive.length).trim());
  };

  Parser.prototype.parseFilter = function (src) {
      src = src.trim();
      var match = src.match(/[:(]/);
      var i = match ? match.index : -1;
      if (i < 0) return JSON.stringify([src]);
      var name = src.slice(0, i);
      var args = src.charAt(i) === ':' ? src.slice(i + 1) : src.slice(i + 1, -1);
      args = this.parseExpr(args, {terms: true});
      return '[' + JSON.stringify(name) + ',' + args + ']';
  };

  Parser.prototype.extractEnt = function (src, regex, placeholder) {
      var subs = [], isFunc = typeof placeholder == 'function';
      src = src.replace(regex, function (str) {
          var replacement = isFunc ? placeholder(str) : placeholder;
          if (replacement) {
              subs.push(str);
              return replacement;
          }
          return str;
      });
      return {src: src, subs: subs};
  };

  Parser.prototype.injectEnt = function (extracted, placeholder) {
      var src = extracted.src, subs = extracted.subs, isArr = Array.isArray(src);
      var arr = (isArr) ? src : [src];
      var re = new RegExp('[' + placeholder + ']', 'g'), i = 0;
      arr.forEach(function (src, index) {
          arr[index] = src.replace(re, function () {
              return subs[i++];
          });
      });
      return isArr ? arr : arr[0];
  };

  //replace complex literals without mistaking subscript notation with array literals
  Parser.prototype.replaceComplex = function (s) {
      var parsed = this.extractEnt(s, /i(\.i|\[[@#i]\])+/g, 'v');
      parsed.src = parsed.src.replace(NON_PRIMITIVES, '~');
      return this.injectEnt(parsed, 'v');
  };

  //parse expression containing literals (including objects/arrays) and variables (including dot and subscript notation)
  //valid expressions: `a + 1 > b.c or c == null`, `a and b[1] != c`, `(a < b) or (c < d and e)`, 'a || [1]`
  Parser.prototype.parseExpr = function (src, opts) {
      opts = opts || {};
      //extract string literals -> @
      var parsed1 = this.extractEnt(src, STRINGS, '@');
      //note: this will catch {not: 1} and a.is; could we replace temporarily and then check adjacent chars?
      parsed1.src = parsed1.src.replace(EOPS, function (s, before, op, after) {
          return (op in operators) ? before + operators[op] + after : s;
      });
      //sub out non-string literals (numbers/true/false/null) -> #
      // the distinction is necessary because @ can be object identifiers, # cannot
      var parsed2 = this.extractEnt(parsed1.src, IDENTS_AND_NUMS, function (s) {
          return (s in constants || NUMBER.test(s)) ? '#' : null;
      });
      //sub out object/variable identifiers -> i
      var parsed3 = this.extractEnt(parsed2.src, IDENTIFIERS, 'i');
      //remove white-space
      parsed3.src = parsed3.src.replace(/\s+/g, '');

      //the rest of this is simply to boil the expression down and check validity
      var simplified = parsed3.src;
      //sub out complex literals (objects/arrays) -> ~
      // the distinction is necessary because @ and # can be subscripts but ~ cannot
      while (simplified !== (simplified = this.replaceComplex(simplified))) ;
      //now @ represents strings, # represents other primitives and ~ represents non-primitives
      //replace complex variables (those with dot/subscript accessors) -> v
      while (simplified !== (simplified = simplified.replace(/i(\.i|\[[@#i]\])+/, 'v'))) ;
      //empty subscript or complex variables in subscript, are not permitted
      simplified = simplified.replace(/[iv]\[v?\]/g, 'x');
      //sub in "i" for @ and # and ~ and v (now "i" represents all literals, variables and identifiers)
      simplified = simplified.replace(/[@#~v]/g, 'i');
      //sub out operators
      simplified = simplified.replace(OPERATORS, '%');
      //allow 'not' unary operator
      simplified = simplified.replace(/!+[i]/g, 'i');
      var terms = opts.terms ? simplified.split(',') : [simplified];
      terms.forEach(function (term) {
          //simplify logical grouping
          while (term !== (term = term.replace(/\(i(%i)*\)/g, 'i'))) ;
          if (!term.match(/^i(%i)*/)) {
              throw new Error('Invalid expression: ' + src + " " + term);
          }
      });
      parsed3.src = parsed3.src.replace(VARIABLES, this.parseVar.bind(this));
      parsed2.src = this.injectEnt(parsed3, 'i');
      parsed1.src = this.injectEnt(parsed2, '#');
      return this.injectEnt(parsed1, '@');
  };

  Parser.prototype.parseVar = function (src) {
      var args = Array.prototype.slice.call(arguments);
      var str = args.pop(), index = args.pop();
      //quote bare object identifiers (might be a reserved word like {while: 1})
      if (src === 'i' && str.charAt(index + 1) === ':') {
          return '"i"';
      }
      var parts = ['"i"'];
      src.replace(ACCESSOR, function (part) {
          if (part === '.i') {
              parts.push('"i"');
          } else if (part === '[i]') {
              parts.push('get("i")');
          } else {
              parts.push(part.slice(1, -1));
          }
      });
      return 'get(' + parts.join(',') + ')';
  };

  //escapes a name to be used as a javascript identifier
  Parser.prototype.escName = function (str) {
      return str.replace(/\W/g, function (s) {
          return '$' + s.charCodeAt(0).toString(16);
      });
  };

  Parser.prototype.parseQuoted = function (str) {
      if (str.charAt(0) === "'") {
          str = str.slice(1, -1).replace(/\\.|"/, function (s) {
              if (s === "\\'") return "'";
              return s.charAt(0) === '\\' ? s : ('\\' + s);
          });
          str = '"' + str + '"';
      }
      //todo: try/catch or deal with invalid characters (linebreaks, control characters)
      return JSON.parse(str);
  };


  //the context 'this' inside tagHandlers is the parser instance
  var tagHandlers = {
      'if': function (expr) {
          this.push('if (' + this.parseExpr(expr) + ') {');
          this.nest.unshift('if');
      },
      'else': function () {
          if (this.nest[0] === 'for') {
              this.push('}, function() {');
          } else {
              this.push('} else {');
          }
      },
      'elseif': function (expr) {
          this.push('} else if (' + this.parseExpr(expr) + ') {');
      },
      'endif': function () {
          this.nest.shift();
          this.push('}');
      },
      'for': function (str) {
          var i = str.indexOf(' in ');
          var name = str.slice(0, i).trim();
          var expr = str.slice(i + 4).trim();
          this.push('each(' + this.parseExpr(expr) + ',' + JSON.stringify(name) + ',function() {');
          this.nest.unshift('for');
      },
      'endfor': function () {
          this.nest.shift();
          this.push('});');
      },
      'raw': function () {
          this.rawMode = true;
      },
      'endraw': function () {
          this.rawMode = false;
      },
      'set': function (stmt) {
          var i = stmt.indexOf('=');
          var name = stmt.slice(0, i).trim();
          var expr = stmt.slice(i + 1).trim();
          this.push('set(' + JSON.stringify(name) + ',' + this.parseExpr(expr) + ');');
      },
      'block': function (name) {
          if (this.isParent) {
              ++this.parentBlocks;
              var blockName = 'block_' + (this.escName(name) || this.parentBlocks);
              this.push('block(typeof ' + blockName + ' == "function" ? ' + blockName + ' : function() {');
          } else if (this.hasParent) {
              this.isSilent = false;
              ++this.childBlocks;
              blockName = 'block_' + (this.escName(name) || this.childBlocks);
              this.push('function ' + blockName + '() {');
          }
          this.nest.unshift('block');
      },
      'endblock': function () {
          this.nest.shift();
          if (this.isParent) {
              this.push('});');
          } else if (this.hasParent) {
              this.push('}');
              this.isSilent = true;
          }
      },
      'extends': function (name) {
          name = this.parseQuoted(name);
          var parentSrc = this.readTemplateFile(name);
          this.isParent = true;
          this.tokenize(parentSrc);
          this.isParent = false;
          this.hasParent = true;
          //silence output until we enter a child block
          this.isSilent = true;
      },
      'include': function (name) {
          name = this.parseQuoted(name);
          var incSrc = this.readTemplateFile(name);
          this.isInclude = true;
          this.tokenize(incSrc);
          this.isInclude = false;
      }
  };

  //liquid style
  tagHandlers.assign = tagHandlers.set;
  //python/django style
  tagHandlers.elif = tagHandlers.elseif;

  var getRuntime = function runtime(data, opts) {
      var defaults = {autoEscape: 'toJson'};
      var _toString = Object.prototype.toString;
      var _hasOwnProperty = Object.prototype.hasOwnProperty;
      var getKeys = Object.keys || function (obj) {
          var keys = [];
          for (var n in obj) if (_hasOwnProperty.call(obj, n)) keys.push(n);
          return keys;
      };
      var isArray = Array.isArray || function (obj) {
          return _toString.call(obj) === '[object Array]';
      };
      var create = Object.create || function (obj) {
          function F() {
          }

          F.prototype = obj;
          return new F();
      };
      var toString = function (val) {
          if (val == null) return '';
          return (typeof val.toString == 'function') ? val.toString() : _toString.call(val);
      };
      var extend = function (dest, src) {
          var keys = getKeys(src);
          for (var i = 0, len = keys.length; i < len; i++) {
              var key = keys[i];
              dest[key] = src[key];
          }
          return dest;
      };
      //get a value, lexically, starting in current context; a.b -> get("a","b")
      var get = function () {
          var val, n = arguments[0], c = stack.length;
          while (c--) {
              val = stack[c][n];
              if (typeof val != 'undefined') break;
          }
          for (var i = 1, len = arguments.length; i < len; i++) {
              if (val == null) continue;
              n = arguments[i];
              val = (_hasOwnProperty.call(val, n)) ? val[n] : (typeof val._get == 'function' ? (val[n] = val._get(n)) : null);
          }
          return (val == null) ? '' : val;
      };
      var set = function (n, val) {
          stack[stack.length - 1][n] = val;
      };
      var push = function (ctx) {
          stack.push(ctx || {});
      };
      var pop = function () {
          stack.pop();
      };
      var write = function (str) {
          output.push(str);
      };
      var filter = function (val) {
          for (var i = 1, len = arguments.length; i < len; i++) {
              var arr = arguments[i], name = arr[0], filter = filters[name];
              if (filter) {
                  arr[0] = val;
                  //now arr looks like [val, arg1, arg2]
                  val = filter.apply(data, arr);
              } else {
                  throw new Error('Invalid filter: ' + name);
              }
          }
          if (opts.autoEscape && name !== opts.autoEscape && name !== 'safe') {
              //auto escape if not explicitly safe or already escaped
              val = filters[opts.autoEscape].call(data, val);
          }
          output.push(val);
      };
      var each = function (obj, loopvar, fn1, fn2) {
          if (obj == null) return;
          var arr = isArray(obj) ? obj : getKeys(obj), len = arr.length;
          var ctx = {loop: {length: len, first: arr[0], last: arr[len - 1]}};
          push(ctx);
          for (var i = 0; i < len; i++) {
              extend(ctx.loop, {index: i + 1, index0: i});
              fn1(ctx[loopvar] = arr[i]);
          }
          if (len === 0 && fn2) fn2();
          pop();
      };
      var block = function (fn) {
          push();
          fn();
          pop();
      };
      var render = function () {
          return output.join('');
      };
      data = data || {};
      opts = extend(defaults, opts || {});
      var filters = extend({
          html: function (val) {
              return toString(val)
                  .split('&').join('&amp;')
                  .split('<').join('&lt;')
                  .split('>').join('&gt;')
                  .split('"').join('&quot;');
          },
          safe: function (val) {
              return val;
          },
          toJson: function (val) {
              if (typeof val === 'object') {
                  return JSON.stringify(val);
              }
              return toString(val);
          }
      }, opts.filters || {});
      var stack = [create(data || {})], output = [];
      return {
          get: get,
          set: set,
          push: push,
          pop: pop,
          write: write,
          filter: filter,
          each: each,
          block: block,
          render: render
      };
  };

  var runtime;

  jinja.compile = function (markup, opts) {
      opts = opts || {};
      var parser = new Parser();
      parser.readTemplateFile = this.readTemplateFile;
      var code = [];
      code.push('function render($) {');
      code.push('var get = $.get, set = $.set, push = $.push, pop = $.pop, write = $.write, filter = $.filter, each = $.each, block = $.block;');
      code.push.apply(code, parser.parse(markup));
      code.push('return $.render();');
      code.push('}');
      code = code.join('\n');
      if (opts.runtime !== false) {
          runtime = runtime || (runtime = getRuntime);
      }
      var render = new Function('object', 'return ('+code+')(object)');
      var fn = function (data, options) {
          return render(runtime(data, options));
      }
      return {render: fn};
  };
  jinja.render = function (markup, data, opts) {
      var tmpl = jinja.compile(markup);
      return tmpl.render(data, opts);
  };

  jinja.templateFiles = [];

  jinja.readTemplateFile = function (name) {
      var templateFiles = this.templateFiles || [];
      var templateFile = templateFiles[name];
      if (templateFile == null) {
          throw new Error('Template file not found: ' + name);
      }
      return templateFile;
  };


  /*!
   * Helpers
   */

  function trimLeft(str) {
      return str.replace(LEADING_SPACE, '');
  }

  function trimRight(str) {
      return str.replace(TRAILING_SPACE, '');
  }

  function matchAll(str, reg, fn) {
      //copy as global
      reg = new RegExp(reg.source, 'g' + (reg.ignoreCase ? 'i' : '') + (reg.multiline ? 'm' : ''));
      var match;
      while ((match = reg.exec(str))) {
          var result = fn(match[0], match.index, str);
          if (typeof result == 'number') {
              reg.lastIndex = result;
          }
      }
  }
}));

export default jinja;
